X-ray inspection apparatus



Nov. 16, 1937. M. B. ADRIAN x-RAY INSPECTION APPARATUS Filed Sept. l, 1954 2 SheetS-Sheet 1 lNvl-:NToR www f3. @hwy @M/MV ATToRNi-:Ys

Nov. 16, 1937.

M. B. ADRiAN 2,099,185

X-RAY INSPECTION APPARATUS 2 Sheets-Sheet 2 Filed sept. 1, 1954 Z INVENTOR Mzzm/ am BY 30 M, maar MM ATTORNEYS Patented Nov. 16, 1937 A UNI TE D STAT .es

X-RAYiNsPEoTIoN APPARATUS l VMatthew B. Adrian, Milwaukee, wis.,assignor tb X-Ray Shoe Fitter,

corporation of: Wisconsinf y i AApplication September f x 12 Claims.

This invention relates to improvements in X- ray inspection apparatus. This is a continuation in part of my application Serial No. 539,226 filed May 22, 1 931. l

It is the primary object of this invention to provide inspection apparatus for theX-ray examination of allsorts of natural and manufactured objects in a manner that is practical from a commercial production standpoint, and without exposing the operator or his fellow workmen to the X-ray. v

The matter of adequate protection is a serious one, but the present invention not only affords such protection but it is nevertheless adaptable to the examination of a number of widely differ. 'ing objects of various sizes and shapes. f

Other objects of the invention include t he pro- Vision of a novel means formarking a ydefective article for discard; the provision of an arrangement permitting the adjustment of the apparatus to suit the convenience of inspectors of different heights; thevprovision of means for adjusting the apparatus for most effective use of articles of different sizes and shapes; the provision of means for cutting oiT the branching beams and using primarily only the direct beams of the X-ray; the provision of a convenient and compact organization wherein the entire X-ray and motive apparatus is housed between the advancing and returning flights of an endless conveyor;V and the provision of means for permitting the ingress of articles to the viewing chamber and their egress therefrom without the escape of X-rays. v

In the drawings:

Figure 1 is a View of a device embodying my invention, partially in front elevation and partially exposing the interior mechanism by breaking away and removing the front wall of the housing.

I Figure2 is a plan view of the apparatus shown in Figure 1.

Figure 3 is a vertical section on an enlarged scale, taken in the plane indicated at 3--3 in Figure 2. Y

Figure 4 is a fragmentary detail in horizontal section on an'enlarged scale, showing the mount ings upon which the fluoroscopic screen and mirror are individually adjustable.

Figure 5 is a detail View in cross section showing the housing for the X-ray tube.

Figure 6 is a detail view partially in side eleva-l tion and partially 'in section, showing on an enlargedV scale the marking device which isa part of the present apparatus.` j

Inc., Milwaukee, Wis., a

1, @34, lserial No; 742,439 .(01.250-340 Like parts are identified by the same reference charactersthroughoutthe several views.

v.The device is conveniently assembled yabout any suitable frame such as that shown at 8 in Figs. 1 and 3. Suitable guides such as maybe made of angle irons 9 support-the -margins of the wood conveying'` flight of a conveyor ID which runs over'pulleysV H, I2, I3 and |4.- The return flight is carried by vsuitable angle iron guides l5. Any desired Vformof conveyor may be used. I have found it convenient to employ a canvas belt. conveyor 4with suitable work propelling lugs in the form'of wooden vstrips I6 fastened to the surface of the belt at-short intervals. While any suitable means maybe employed 'for propelling the^conveyor, it is very desirable that the conveyor Y'should .be atjall times under control ofY the'.i n spect`or so that he may start the conveyor independently ofthe X-ray apparatus for the prolonged examination of a given article when necessary. j Conveniently, therefore, the conveyor is operated` by a motor I1 wli'ichdrivesY pulley l2 through a belt Afl8 and reduction ygearing i9, the mode of circuitV being subject to control by means of switch 20. vThe switch is shown to be located 2 at the level of the conveyor withits control lever in easy reachof thexoperators left hand.

Directly below lthe top flight of conveyor I0 at the inspection Tstation is the X-ray tube V25 Which,f`for convenience `of* mounting and con#A nection, is preferably setdiagonally as shown in l 2. The tubeis enclosed in a case 26 having pointed ends and providedfat 28 with a removable front through Whichnthe tube is accessible, the closure 28` and case 26 having a lead sheet or lining 2,9 throughout to prevent the undesired escape of X-ray emissions from the tube. The case has ventilation openings at 3|) shielded by lead bailes 3l for the escape of cooling air which is blown into? the' case through a conduit 32 by means o f a; fan 33 carried on the shaft of motor l1. There is,` of course, an opening in the lead lining 29 at the` top of case 26, toward which the yprimary emission of tube 25 is directed.

\ v The control panel 35, switch 36, transformer 31, rectifier '38, and suitable vconnections to the tube 25ar'e illustrated but are not shown in de-V tail, `being' well known in the art. All of this' apparatus is housed within the closed pathof travel of theV 'endless conveyor |0', the front and back sides of the space in which vthisapparatus is 4assembled being enclosed, in completedA machines, by front and rear panels 38 and 39.

Mounted upon the housing 26 for the X-ray tube is aV bellows-like cone 40 which extends upwardly into substantial contact with the lower surface of the top flight of the conveyor I0. The convolutions in the walls of the generally pyramidal enclosure 40 are not for expansion or contraction, but serve as traps to intercept lateral radiations branching from the principal X-ray beams emitted by the tube. The angles of the convolutions are preferably approximately as illustrated in Fig. 3, so that any reflection of .these branching radiations will throw them back into the shielded casing 26 instead of permitting them to reach some point from which they might escape from the machine. Above that portion of the conveyor luthrough.

which the X-rays are projected at, thelviewing station, is a viewing chamber 42 having its top and side wall portions provided with lead sheathing at 43. A forward extensionV 44 of this chain;`

ber carries an eye piece 45 through which the operator may look into the interior of the chamber without being exposed to X-rays passing upwardly therein. The extension 44 may conveniently be made of lead plated or coated metal.

The whole chamber 42 and its appurtenances are guided for vertical movement; As a convenient arrangement I have shown xed posts 46 at diagonally opposite corners of the chamber 42, and screws 41 at the other two corners. The chamber is provided with apertured arms 48 riding on the posts 46 and with nuts 49 meshing with the screws 41. Upon a crosshead 50 mounted on the posts 46 and provided with bearings for the screws 41, is an operating shaft 5l' connected by bevel gearing at 52 with the screws 41 and adapted for rotation by means of crank 53 to turn the screws 41 and thereby .to raise and lower the chamber 42. The machirueVV frame is slotted at 54 to receive a lead panel 55 which is connected with chamber 42 and is of such length as to overlap the bellows-like housing 40 in all positions of adjustment of theY viewing chamber 42, thereby assuring the protection of the operator from stray rays which might otherwise escape when the chamber was. elevated.v

Also connected with the viewing chamberare the canopies 51 and 58 comprising a longitudinal enlargement of the chamber alongy thepath` ofthe conveyor l0. 'I'hese canopies, likev the. rest of. the. chamber, are. lined with the leadsheathing 43.-

Theirprojection is sucient to ensure againstthe.-

escape of X-rays from the viewing chamber at the points where articles on the conveyor enter. into the viewing` chamber.

To permit the ingress and egress of articles. to be inspected, the viewing chamber is provided with openings overhung by the canopies 51 and 58. These openings are flexibly closed by aA lead coat-y ed curtain of rubber or other suitable exible material, as shown at 6D and 6| in Figs, 1 and 3. These curtains, being somewhat heavy. offer appreciable resistance to the movement of an article on the belt but the wooden lugs I 6 on the belt assure. the continued movement of the-ar.- ticles carried thereby. j

The fluorescent screen 62 is preferably-pivoted upon an axis 63 about which itis movable by means of a suitable control lever- 64 ywhich may be anchored with reference to a conventional segment. If small articles are being examined the screen may be so adjusted that its forward portion will be very close to the surface of the belt. If large articles, such as hams, or other articles of irregular shape, are being examined, the screen may be adjusted to approximate parallelism With the path followed by the upper surfaces of such articles. The range of adjustment will be such as to give the best X-ray vision of a variety of products within the capacity of the machine. The screen eifects a division of the hood or viewing chamber proper which is above the screen, from the enclosure below the screen and within the panels 55 and curtains 60 through which pass the articles to be inspected.

Pivotally adjustable upon the same axis 63 (or -upon any other suitable axis), is a mirror 65, the

angle of which is adjustable un-der the control of handle 66, the segment of which is shown at 61. The. mirror is of a type which does not intercept 'or reflect X-rays but does reect light from the fluorescent screen to the eye piece 45 through which the operator views the articles under examination. VThe Vadjustment of the mirror not only, -compensates for variations in position of the screen, but also compensates for. variations in position of the viewing chamber 42 in its vertical adjustment, so that the operator may sit or stand as he desires.

If the operator had to reach into the apparatus for the removal of a defective article found by his X-ray examination, Vhe would not only expose his hand to danger of serious X-ray burns, but he would seriously retard the progress of his work. In order to make any such removal of the defective articles unnecessary, I provide the viewing chamber 42 with a universal mounting at 69 for a, marking device located in the enclosure below the screen, the marking de- Vvice being designated by reference character 1Q as shown more particularly in Fig. 6. A tube 1l is reciprocable through an opening in the universal mounting and-has its inner end portion 12 bent approximately at right angles in a normally hoi-izontal'plane. At the outer end of the tube, the tube communicates with a container 13 for marking fluid, the shape of the container adapting it to serve as a handle for the manipulation of the marking device. A removable closure at 14 permits the renewal of the marking uid from time to time.

A wick 15 has its end within the container 13 and extends through the tube 10 to project from the end 12 thereof. Not only does the wick carry the marking flui-d through the open end 12 of the tube by capillarity, but, since the container 13 serves as a handle, it will be obvious that every timethe handle is oscill'ated to turn downwardly the curved end 12 of the tube, the liquid contents of the container 13 will to some degree be discharged along the wick into the tube toward the end from which the wick projects.

Obviously, the operator is able to use this marking device to place a spot of marking fluid upon each defective article passing through the inspecting station. The articles so marked can be removed separately from the conveyor by some other person and discarded, thus leaving the inspector unharmed in his continuous observation of the articles carried by the conveyor I0.

Articles such as shoes may conveniently be inspected to determine whether nails used temporarily for lasting purposes have inadvertently been allowed to remain in the shoe. Objects such as oranges may be inspected to determine whether or not they are juicy or pulpy. Objects such as hams may be inspected to determine whether or not the marrow is sound or spoiled. Those articles specificallyV mentioned are chosen t0 illustrate the wide range or shapes of materials which may be examined in this single piece of apparatus.

In all examinations the inspector is fully protected from the menace of the X-ray tube. Not l emanations passing the screen'cannot reach his Y eyes. Thearrangement is such that the articles enter and leave the viewing chamber without permitting the escape of rays.

The disposition of the X-ray and mode of mechanism between thevconveyor nights has the advantage that the upper surface of the conveyor is fully exposed at both ends of the apparatus for the mounting and removal of the articles requiring inspection. The X-rays do not have to pass through more than one flight of the conveyor and the tube is locatedin the-best position with reference to the articles on the con-V veyor.

The X-ray tube is sufficiently close to Vthe path of movement of ther articles to be inspected so that the emanations of the tube pass through the articles at a wide variety of angles. Assuming the articles tovbe' movingrfrom left to right in Fig. l, at the time when the article nrst appears beneath the nuoroscopic screen within the path moment, the operator is able to see eacharticle,

in effect, from a constantly changing viewpoint in the course of its travel through the machine, the effect being the same as if the articles were held above the tube andturned from side to side.

While a conventional belt conveyor has been illustrated for the purpose of exemplifying the present invention, it will be obvious to those skilled in the art that such articles as oranges, and many other articles requiring inspection, are capable of propelling themselves by gravity along a conveyor which comprises a mere trough for the guidance of such articles. Manyother changes may be made Without departure from the spirit of the invention which is merely exemplified by the apparatus herein described.

I claim:

i. X-ray inspectionapparatus comprising the combination with a conveyor for propelling in a predetermined path thearticles requiring inspection, and means for actuating said conveyor during inspection of articles thereon, of an X-ray tube arranged todischarge immediatelyV across said path, an X-ray sensitive screen operativelyv disposed opposite said tube adjacent said path, a viewingY chamber enclosing said screen lfor the exclusion of extraneous light and provided with inlet and outlet openings throughV which said articlesmove, and ray connning means at said inlet and outlet through which said conveyor and articles are freely movable.

2. X-ray inspection apparatus comprising the ately at said work supporting night, and an X- ray sensitive screen operatively positioned at the other side of said flight to intercept rays traversing work thereon, means substantially impervito said Work supporting conveyor flight about Vthe path of discharge of said tube, shielding means extending from said screen .to said conveyor flight and provided with means for the ingress and egress of work thereon, and means for .actuating said conveyor for the advance of work between said tube and screen during inspection thereof. i

Y. 3. X-ray inspection apparatus comprising the combination with a work propelling conveyor flight, of an X-ray tube therebeneath arranged to interceptV rays Ifromxsaid tube, a mirrr extending -angularly above said screen and arranged to renect laterally 'the light emanating from the screen, and means forlshielding the inspector from X-rays, said means including a viewing chamber enclosing said screen and the path of work exposedto said X-rays and pro.- vided with a lateral sight opening through which the image of said screenin said Inirror is visible, said conveyor night being provided with means for the continuous propulsion of work through said chamber.

4. X-ray inspection apparatus comprising the combination with a work propelling conveyor night, of an X-ray discharge tube immediately therebeneath, a fluoroscopic screen spaced above said night, aV viewing chamber enclosing said screen, means for adjusting said chamber and rous to X-rays enclosing said tube and extending f5 1 f to discharge upwardly acrossthe path of an article propelled Vby said night,an X-ray sensitive screen disposed above said path in a position screen to and from said night, and shielding means extending continuously between said flight andV said chamber and operative to corinne the emission from said tube in all adjustments of said chamber.

5. X-ray-inspection apparatus comprising the combination with a work propelling conveyor night, of an X-ray discharge tube disposed immediately therebeneath with its discharge directed upwardly across the path of materials propelled by said night, a nuoroscopic screen spaced above said path, a viewing chamber projecting above said screen and extending about said screen to said night, a mirror adjustable as to angle disposed in said viewing chamber for the Y lateral reflection of `the image of said screen, and

a lateral extension of said viewing chamber provided with an inspection opening.

6. The combination with a conveyor night for the continuous propulsion of material to be inspected, and means for effecting continuous propulsion of work on said night, of an X-ray tube at one side of said night, a screen at the other side of the flight and an enclosure substantially opaque to X-rays between said screen and said night provided with openings for the ingress and egress of material propelled by said night and means at said openings for intercepting X-rays and preventing their escape from said enclosure during the passage of such material into and out of the enclosure.

7. The combination with a conveyor night for the propulsion of material to be inspected, and means for propelling material on said night during inspection, of an X-ray tube at one side of said flight, a screen at the other and an enclosure substantially opaque to X-rays between said screen and said night provided with openings for the ingress and egress of material propelled on sai-d ight, said openings having X-ray obstructing closures movable under pressure of said material in entering' and leaving said enclosure.

8. X-ray inspection apparatus comprising the combination with a conveyor, of an X-ray tube arranged to discharge across the path of mate. rials thereon, a screen operatively positioned across said path from said tube and 'immediately adjacent said path, means for adjusting said screen angularly with respect to said path, an-d a viewing chamber enclosing said screen and provided with a mirror and a sight opening through which the image ,of said screen is visible in the mirror.

9. X-ray inspection apparatuns comprising the combination with a conveyor, of an X-raytube arranged to discharge across the path of articles on the conveyor, a fluorescent screen operatively positioned across said path from said tube, a viewing chamber enclosing said screen and bodily movable to and from said path, and means extending the wall portions of said viewing chamber to said conveyor and provided with shielding effective in all positions of said chamber to enclose the space between said conveyor and screen.

10. X-ray inspection apparatus comprising the -combination With a conveyor, of an X-ray tube arranged to discharge across the path of articles on the conveyor, a fluorescent screen operatively positioned across said path from said tube, a viewing chamber enclosing said screen and bodily movable to and from said path, and means extending the wall portions of said viewing cham ber to said conveyor and provided with shielding effective in al1 positions of said chamber to enclose the space between said conveyor and screen, said means including lead treated curtains in the path of articles entering and leaving said means.

ll. X-ray inspecting mechanism comprising the combination with a shielded and apertured enclosing means, of a conveyor flight arranged to pass articles into and out of said means through the apertures thereof, means for the continuous actuation of the conveyor night during inspection, Xfray trapping means associated with each of said apertures for permitting the continuous movement of articles on the conveyor `ilight into and out of the enclosing means while affording substantially continuous protection against the escape of X-rays therefrom, an X-ray tube at one side of thepath oi articles through said means, and a viewing screen at the other side of the path of articles through said enclosing means, said tube and screen being within said enclosing means, and said enclosing means being extended about said screen to intercept direct rays of extraneous light and provided with an opening for the use of an operator through which said screen is visible for the inwspectionv of the images thereon of successive articles advanced by said conveyor flight.

l2. X-ray inspection .apparatus comprising the combination with a continuously movable conveyor and means for the continuous actuation thereof during inspection, said, conveyor being adapted for the propulsion of material requiring inspection, of an X-ray tube arranged to discharge immediately across the path of the material to be inspected as such material moves upon the conveyor, a screen sensitive to X-rays operatively disposed opposite the tube adjacent said path, a viewing chamber enclosing the screen for the exclusion of extraneous light and including X-ray shielding means enclosing the path of material moving with said. conveyor between the X-ray tube and screen, said shielding means having inlet and outlet portions through which said conveyor and the materials proelled thereby are freely movable during the continuous operation of the conveyor.

l MATTHEW B. ADRIAN. 

